Week of 10/21/13

Monday: Unit 3 Gases and limiting reactant test day!

Tuesday: Maxwell Boltzmann Distribution lesson.  Here’s a link to my lecture!

Wednesday: PhET simulation for collision theory. Notes on collision theory.  HW: read about catalytic convertor. Video on catalytic converter.  A movie to explain today’s concepts.  Another movie that mixes Maxwell Boltzmann and the PE diagram.

Thursday: Today we started with CA 36 to learn how to calculate reaction rates and use stoichiometry to get reaction rate of one product or reactant when another is known.  Then we went over a graph of concentration vs. time and explained the shape. Next we used this animation thing to show what is meant by instantaneous rate.  Lastly I lectured on how to determine the rate law.  Here’s the notes (after collision theory) + these powerpoint notes.  A video for today’s lesson.

 

Friday: We did a quick practice question with a reaction rate graph and then went over how to figure out units for rate constants. The rest of class we worked on CA 57.  Here’s the answer key.

Week of 10/14/13

Monday: Teacher professional day

Tuesday: Went over the AP problems from Friday. That took all class. Homework was to continue with whatever problems haven’t been finished, feel free to read!

Wednesday: Went over solving stoichiometry problems with only volumes of gases. The big idea is that because a given volume has the same number of particles (moles) at a given P and T, you can treat volumes like moles in stoichiometry problems as long as the pressure and temperature stay the same.   (This is for volume to volume problems only.)  Next we went over 5.27 and 5.28 from your homework.  You talked about it in groups and then we went over a couple of the tricky ideas.  1) the mass of the molecules doesn’t matter when it comes to pressure because the pressure depends only on the # of particles, not their identity.  Even heavier gases would have the same pressure (assuming same T and V).  If they are at the same temperature, they will have the same energy and therefore will hit the sides with the same amount of force.  This leads us to the second tricky idea 2) the mass does affect speed of the molecules.  Molecules or atoms at the same temperature have the same kinetic energy (temperature is a measure of kinetic energy). So, since KE = 1/2mv^2, where m = mass and v = velocity or speed, if 2 molecules have the same energy but one has a larger mass, it must have a smaller speed in order to have the same energy.   The 3rd tricky idea had to do with surface area.  It seems as though molecules in a shape with more surface area would collide with the surface more often and that might make you think the pressure is higher, but Pressure = Force / Area, so the increase in force from additional collisions is balanced by the increase in surface area.  We did a few more practice problems involving proportions.  We reviewed which variables were inversely and which were directly proportional and also some mole fraction / Dalton’s law problems.

During the second half of class we went over the Dumas method for determining in the molar mass of a volatile gas. This included a discussion of how to think about error analysis when writing your conclusions.  We ended with a problem that mixed the Dumas method with empirical and molecular formula.

HW: Finish all your homework!

Thursday: Do PhET simulation for gases.  Goal is to collect data that shows pressure and volume have an inverse relationship.  Include design 1 items from checklist, collect quantitative and qualitative data, graph data and include a discussion that justifies your claim that pressure and volume have an inverse relationship.  A second goal is to collect data that shows how absolute zero is derived.  You should include items from Design 1 on checklist as well as quantitative and qualitative data (do not measure absolute zero diretly)  + a graph showing how you use it to get absolute zero. Your graph need to have the temperature in celsius.

Friday: Today we worked on the rest of the AP problems.  Some of you worked on a study guide instead. Homework to be collected is all textbook problems and AP Free response problems.

Week of 10/6/13

Monday: Limiting reactant and rxns of gases quiz. Rest of block to do Ideal Gas constant lab.

Tuesday and Wednesday: I was out so you worked on this stuff.

Thursday: Finish Ideal gas constant lab and work on any homework problems you haven’t done yet!

Friday: Went over your limiting reactant test. Gas demos and the difference between Ideal and real gases. (Here’s the notes including answers to quiz).

Homework is to do the textbook problems on the unit outline for Thursday (covers gas laws and real vs. ideal). Do AP Free Response 1982, 1984, 1990. Here’s the answers for AP Problems. (not in order, look for the year)
Also, the NMSI lady has a video going over the AP problems. part 1  part 2

Week of 9/30/13

Monday: We started the limiting reactant and gases unit with a micromole rockets lab. I did this because it introduces you to some more types of reactions and gives you a real feel for the idea of limiting reactants.

HW: Do pg 13-14 in your double displacement packet and review limiting reactant problems.

Tuesday: I was hoping to hand out the unit outline, but it wasn’t done by class time. Here’s a copy for those of you that were absent and need the homework problems.  The first part of class I gave notes on various types of reactions and then you worked on limiting reactant problems.

Homework: Finish problems (see unit outline)

Wednesday: For the first part of class we did a chemical formulas lab. The point is for you to see how you can use the method of continuous variations and the concept of limiting reactants to determine the chemical formula of a compound.  The second half of class we talked about gases and how we measured them.  I did a couple PV=nRT problems and a couple stoichiometry problems with PV=nRT.  Notes from class.

Homework: 3 PV=nRT with stoich problems (See unit outline)